PM: Add missing syscore_suspend() and syscore_resume() calls

Device suspend/resume infrastructure is used not only by the suspend
and hibernate code in kernel/power, but also by APM, Xen and the
kexec jump feature.  However, commit 40dc166cb5dddbd36aa4ad11c03915ea
(PM / Core: Introduce struct syscore_ops for core subsystems PM)
failed to add syscore_suspend() and syscore_resume() calls to that
code, which generally leads to breakage when the features in question
are used.

To fix this problem, add the missing syscore_suspend() and
syscore_resume() calls to arch/x86/kernel/apm_32.c, kernel/kexec.c
and drivers/xen/manage.c.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

4 files changed, 22 insertions, 1 deletions

diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c
index 0b4be431c620..adee12e0da1f 100644
--- a/arch/x86/kernel/apm_32.c
+++ b/arch/x86/kernel/apm_32.c
@@ -228,6 +228,7 @@
 #include <linux/kthread.h>
 #include <linux/jiffies.h>
 #include <linux/acpi.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
@@ -1238,6 +1239,7 @@ static int suspend(int vetoable)
 
         local_irq_disable();
         sysdev_suspend(PMSG_SUSPEND);
+        syscore_suspend();
 
         local_irq_enable();
 
@@ -1255,6 +1257,7 @@ static int suspend(int vetoable)
                 apm_error("suspend", err);
         err = (err == APM_SUCCESS) ? 0 : -EIO;
 
+        syscore_resume();
         sysdev_resume();
         local_irq_enable();
 
@@ -1280,6 +1283,7 @@ static void standby(void)
 
         local_irq_disable();
         sysdev_suspend(PMSG_SUSPEND);
+        syscore_suspend();
         local_irq_enable();
 
         err = set_system_power_state(APM_STATE_STANDBY);
@@ -1287,6 +1291,7 @@ static void standby(void)
                 apm_error("standby", err);
 
         local_irq_disable();
+        syscore_resume();
         sysdev_resume();
         local_irq_enable();
 
diff --git a/drivers/base/syscore.c b/drivers/base/syscore.c
index 90af2943f9e4..c126db3cb7d1 100644
--- a/drivers/base/syscore.c
+++ b/drivers/base/syscore.c
@@ -73,6 +73,7 @@ int syscore_suspend(void)
 
         return ret;
 }
+EXPORT_SYMBOL_GPL(syscore_suspend);
 
 /**
  * syscore_resume - Execute all the registered system core resume callbacks.
@@ -95,6 +96,7 @@ void syscore_resume(void)
                                 "Interrupts enabled after %pF\n", ops->resume);
                 }
 }
+EXPORT_SYMBOL_GPL(syscore_resume);
 #endif /* CONFIG_PM_SLEEP */
 
 /**
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index 1ac94125bf93..a2eee574784e 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -8,6 +8,7 @@
 #include <linux/sysrq.h>
 #include <linux/stop_machine.h>
 #include <linux/freezer.h>
+#include <linux/syscore_ops.h>
 
 #include <xen/xen.h>
 #include <xen/xenbus.h>
@@ -70,8 +71,13 @@ static int xen_suspend(void *data)
         BUG_ON(!irqs_disabled());
 
         err = sysdev_suspend(PMSG_FREEZE);
+        if (!err) {
+                err = syscore_suspend();
+                if (err)
+                        sysdev_resume();
+        }
         if (err) {
-                printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
+                printk(KERN_ERR "xen_suspend: system core suspend failed: %d\n",
                         err);
                 return err;
         }
@@ -95,6 +101,7 @@ static int xen_suspend(void *data)
                 xen_timer_resume();
         }
 
+        syscore_resume();
         sysdev_resume();
 
         return 0;
diff --git a/kernel/kexec.c b/kernel/kexec.c
index 55936f9cb251..87b77de03dd3 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -33,6 +33,7 @@
 #include <linux/vmalloc.h>
 #include <linux/swap.h>
 #include <linux/kmsg_dump.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/page.h>
 #include <asm/uaccess.h>
@@ -1532,6 +1533,11 @@ int kernel_kexec(void)
                 local_irq_disable();
                 /* Suspend system devices */
                 error = sysdev_suspend(PMSG_FREEZE);
+                if (!error) {
+                        error = syscore_suspend();
+                        if (error)
+                                sysdev_resume();
+                }
                 if (error)
                         goto Enable_irqs;
         } else
@@ -1546,6 +1552,7 @@ int kernel_kexec(void)
 
 #ifdef CONFIG_KEXEC_JUMP
         if (kexec_image->preserve_context) {
+                syscore_resume();
                 sysdev_resume();
  Enable_irqs:
                 local_irq_enable();